Etablissement Public De Diffusion Dit 'telediffusion De France'

Claude Thomas

Daniel Pommier

Joseph Blineau

A digital data pack transmission system is especially--but not exclusiveluseful in videotex or teletext transmission (i.e. videotext or teletext data is transmitted during intervals between segments of video signals). The inventive system uses a continuous transmission carrier. A plurality of data packs are individually included in each block of data which is periodically transmitted. Dummy packs are used to fill the blocks, if less than a full complement of packs is required. The time periods available for the transmission of blocks of data are exactly equal to or a little longer than the maximum length of the transmitted blocks. The beginning of each data block has a synchronization bit pattern which is constituted by a 'bit sync' byte followed by a 'byte sync' byte. Except for the synchronizing pattern, the signals are scrambled before transmission and descrambled upon receipt and recognization of the data.

Growing community of inventors

Chasne sur Illet, France

Claude Thomas